Systems and methods for providing haptic feedback at multiple resonance frequencies

ABSTRACT

Systems and methods for providing haptic feedback at multiple resonance frequencies are disclosed. For example, one disclosed apparatus includes a resonator with a base and a plurality of projections, a first projection of the plurality of projections having a first resonance frequency and a second projection of the plurality of projections having a second resonance frequency, and a piezoelectric actuator coupled to the resonator and operable to output a haptic feedback effect at the first resonance frequency and at the second resonance frequency.

FIELD OF THE INVENTION

The present invention generally relates to haptic feedback, and moreparticularly to systems and methods for providing haptic feedback atmultiple resonance frequencies.

BACKGROUND

A haptic feedback system vibrating at its resonance frequency may offerseveral advantages, including enhanced haptic feedback effects and/ormore efficient power usage. Conventional haptic feedback systems mayutilize multiple actuators each outputting a vibration at a differentresonance frequency to achieve a system with multiple resonancefrequencies. Using multiple actuators, however, may add weight, use morepower, and cost more than other haptic feedback systems. Accordingly,there is a need for systems and methods for providing haptic feedback atmultiple resonance frequencies.

SUMMARY

Embodiments of the present invention provide systems and methods forproviding haptic feedback at multiple resonance frequencies. Forexample, in one embodiment, an apparatus for providing haptic feedbackat multiple resonance frequencies comprises a resonator comprising abase and a plurality of projections, a first of the plurality ofprojections having a first resonance frequency and a second of theplurality of projections having a second resonance frequency differentfrom the first resonance frequency, and a piezoelectric actuator coupledto the resonator and operable to output a haptic effect at the firstresonance frequency and at the second resonance frequency.

Another embodiment comprises a computer implemented method providinghaptic feedback at multiple resonance frequencies comprising the stepsof receiving an input signal, determining a haptic feedback effect basedat least in part on the input signal, selecting at least one projectionof a plurality of projections of a resonator with which to output thehaptic feedback effect based at least in part on a resonance frequencyof the at least one projection, and generating a haptic signalconfigured to cause a piezoelectric actuator coupled to the resonator togenerate a haptic feedback effect at the resonance frequency. A furtherembodiment of the present invention comprises a computer-readable mediumhaving program code for executing such a computer-implemented method.

These illustrative embodiments are mentioned not to limit or define theinvention, but to provide examples to aid understanding thereof.Illustrative embodiments are discussed in the Detailed Description, andfurther description of the invention is provided there. Advantagesoffered by various embodiments of this invention may be furtherunderstood by examining this specification.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the presentinvention are better understood when the following Detailed Descriptionis read with reference to the accompanying drawings, wherein:

FIG. 1 is a perspective view of an apparatus for providing hapticfeedback at multiple resonance frequencies according to one embodimentof the present invention;

FIG. 2 is a perspective view of an apparatus for providing hapticfeedback at multiple resonance frequencies according to one embodimentof the present invention;

FIG. 3 is a perspective view of an apparatus for providing hapticfeedback at multiple resonance frequencies according to one embodimentof the present invention;

FIG. 4 is a side view of an apparatus for providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention;

FIG. 5 is a top view of an apparatus for providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention;

FIG. 6 is a top view of an apparatus for providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention;

FIG. 7 is a perspective view of an apparatus for providing hapticfeedback at multiple resonance frequencies according to one embodimentof the present invention;

FIG. 8 is a block diagram of a system providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention;

FIG. 9 is an illustration of a system providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention;

FIG. 10 is an illustration of a system providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention;

FIG. 11 is a flow diagram of a method providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention; and

FIG. 12 is a flow diagram of a method providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention.

DETAILED DESCRIPTION

Embodiments of the present invention provide systems and methods forproviding haptic feedback at multiple resonance frequencies.

Illustrative Multi-Resonance Frequency Device

One illustrative embodiment of the present invention comprises a mobiledevice, such as a mobile phone. In the illustrative embodiment, themessaging device comprises the Samsung SGH-i710 mobile computer equippedwith Immersion Corporation's TouchSense® 300 vibrotactile feedbacksystem, previously know as Immersion Corporations VibeTonz® vibrotactilefeedback system. Other messaging devices and haptic feedback systems maybe utilized.

The mobile device comprises a touch-screen display, local memory, and aprocessor in communication with each of these elements. The illustrativemobile device also comprises a resonator and a piezoelectric actuatorcoupled to the resonator and in communication with the processor. Thepiezoelectric actuator is configured to receive a signal from theprocessor and output a haptic effect using the resonator.

In the illustrative device, the resonator is a multi-pronged metal plateor a metal sheet. The resonator comprises a base and two projections—afirst projection and a second projection. Each of the projectionsextends from the base as a cantilevered beam. And each projectioncomprises at least one physical property, such as a shape, a length, awidth, a thickness, a surface, a material composition, or a materialcoating. The resonance frequency of each projection is dependent on thephysical property or properties of the projection. For example, a firstprojection having a first physical property that is different from asecond physical property associated with a second projection may have adifferent resonance frequency. For example, if the first projection hasa different length than a second projection, the two projections willalso likely have a different resonance frequency than the firstprojection.

In the illustrative device, a piezoelectric actuator is coupled to thebase of the resonator and configured to generate a haptic feedbackeffect at the resonance frequencies of each of the projections. Forexample, current may be applied so that a vibration is imparted in thepiezoelectric actuator at the resonance frequency of the projection tobe affected.

The piezoelectric actuator is in communication with the processor, whichgenerates a haptic signal and transmits the haptic signal to thepiezoelectric actuator. The haptic signal causes the piezoelectricactuator to generate a haptic feedback effect by vibrating theresonator. In the illustrative device, some part of the resonator is incontact with the housing or the display of the mobile device. As thepiezoelectric actuator vibrates, a free end of the at least oneprojection bends or flexes up and down, causing the housing or displayto vibrate. In other embodiments, the apparatus may provide hapticfeedback effects to other parts of the mobile device, such as a button.

When the piezoelectric actuator vibrates at a resonance frequency of theprojection in communication with the display, the display outputs anenhanced haptic feedback effect. The effect is enhanced since whileoperating at a resonance frequency of one of the projections, thepiezoelectric actuator requires less power for a given displacement of aprojection. So if the same power is applied, the effect is amplified orenhanced. Because each projection may have a different resonancefrequency, the apparatus may be configured to generate a plurality ofenhanced haptic effects corresponding to each different resonancefrequency.

This illustrative example is given to introduce the reader to thegeneral subject matter discussed herein. The invention is not limited tothis example. The following sections describe various additionalembodiments and examples of systems and methods for providing hapticfeedback at multiple resonance frequencies.

Illustrative Systems for Multiple Resonance Frequency Devices for HapticEffects

Embodiments of the invention presented herein provide systems andmethods for providing haptic feedback at multiple resonance frequencies.The frequency of haptic feedback effects plays an important role in thecharacter, perception, and distinctiveness of a haptic feedback effect.By vibrating at different frequencies, an actuator may provide a varietyof haptic feedback effects that are felt or perceived differently thaneach other. When an actuator vibrates at a resonance frequency of acoupled resonator, the haptic feedback effect may be stronger (i.e. havea greater amplitude) while requiring less power consumption. Thus, byusing systems and methods for providing haptic feedback at multipleresonance frequencies, haptic feedback devices may provide a variety ofenhanced feedback effects.

Illustrative Resonators

Referring now to the drawings in which like numerals indicate likeelements throughout the several Figures, FIG. 1 is a perspective view ofan apparatus for providing haptic feedback at multiple resonancefrequencies according to one embodiment of the present invention. Asshown in FIG. 1, the apparatus 100 comprises a resonator 102 and apiezoelectric actuator 108 coupled to a surface of the resonator 102.

The resonator 102 comprises a base 104 and a plurality of projections106 a, 106 b, and 106 c extending from or coupled to the base 104. Inthe embodiment shown, the base 104 and projections 106 for a singlemonolithic resonator 102. In other embodiments, the projections 106 maybe separate structures affixed to the base 104. The base 104 and/or oneor more of the plurality of projections 106 a, 106 b, and 106 c may beconfigured to generate haptic feedback effects. For example, one or moreof the plurality of projections 106 a, 106 b, and 106 c may be incommunication with a housing of a haptic feedback device (not shown inFIG. 1). When one or more of the projections 106 a, 106 b, 106 cvibrate, the housing of the haptic feedback device may output a hapticfeedback effect, such as a vibration. In other variations, the base 104and/or one or more of the plurality of projections 106 a, 106 b, and 106c are in communication with a keypad, a touchpad, a display, and/orother parts of a haptic feedback device, which output a haptic feedbackeffect.

The resonator 102 may comprise a rigid or semi-rigid metal plate, suchas an aluminum plate or a steel plate. Alternatively, the resonator 102may comprise other materials, such as a flexible or semi-flexibleplastic. In one variation, the resonator 102 comprises a substratecoated with one or more materials. For example, the resonator 102 maycomprise a copper substrate laminated with a silicon polymer. Theresonator 102 may be composed of a material which can be vibrated orflexed by the actuator 108. The shape and/or the material composition ofthe resonator 102 may be selected to effectively integrate into avariety of haptic feedback devices.

The apparatus 100 also comprises a piezoelectric actuator 108 coupled tothe resonator 102 and configured to generate a haptic feedback effect.The piezoelectric actuator 108 may be coupled to the base via a polymermatrix, such as silicon, an epoxy resin, or some other means. Or thepiezoelectric actuator may be coupled to the base 104 via a mechanicalmeans, such as with screws. The piezoelectric actuator may be bonded tothe base 104 and configured to flex and generate vibrations across theentire resonator 102.

In some embodiments, (not shown in FIG. 1) the piezoelectric actuatormay be embedded within a flexible bonding material. The flexible bondingmaterial may have a specific stiffness and damping ratio, and may alsoallow movement in an additional degree of freedom. In such anembodiment, the additional degree of freedom and the stiffness anddamping ratio may allow the system to operate at additional resonantfrequencies. In some embodiments, the present invention may use theseadditional resonant frequencies to generate additional haptic effects.

In FIG. 1, the piezoelectric actuator 108 is shown coupled to a firstsurface of the base 104 of the resonator 102. In another variation, thepiezoelectric actuator 108 is coupled to a second surface of the base104 of the resonator 102. The surfaces may be the top or bottom or thefront and back or another configuration depending on the orientation ofthe resonator 102 in relation to the user. Or a first piezoelectricactuator can be coupled to the first surface of the base 104, and asecond piezoelectric actuator can be coupled to the second surface ofthe base 104. In still other variations, a plurality of piezoelectricactuators 108 may be coupled to the top and/or the bottom of the base104.

The piezoelectric actuator 108 may be in communication with a processor(not shown in FIG. 1). The processor may be configured to determine ahaptic feedback effect and to determine a resonance frequency of atleast one of a plurality of projections 106 a, 106 b, 106 c of theresonator 102. Additionally, the processor may be configured to generatea haptic signal to the piezoelectric actuator 108, the haptic signalconfigured to cause the piezoelectric actuator 108 to generate a hapticfeedback effect at a resonance frequency of a projection 106 a, 106 b,or 106 c.

The piezoelectric actuator 108 may be configured to generate a hapticfeedback effect at each one of the plurality of resonance frequencies ofthe plurality of projections 106 a, 106 b, 106 c. One or more of theprojections 106 a, 106 b, 106 c may be in communication with a hapticfeedback device (not shown in FIG. 1). The projections 106 a, 106 b, 106c may generate a haptic feedback effect on the haptic feedback device byflexing up and down in response to movements by the piezoelectricactuator 108.

The resonator 102 has a first projection 106 a, a second projection 106b, and a third projection 106 c. As shown in FIG. 1, each projection 106a, 106 b, 106 c is affixed to the base 104 and extends from the base104. In one variation, the projections comprise a different materialthan the base 104, and are attached to the base 104 via a couplingmeans, such as an epoxy resin. Each projection 106 a, 106 b, 106 ccomprises a resonance frequency based at least in part on at least onephysical property of the projection. A physical property may comprise alength, a width, a thickness, a surface, a composition, a coating,and/or a shape. For example, the first projection 106 a is a flatrectangle with a first length and a first width. A first resonancefrequency of the first projection 106 a is based at least in part on thefirst length and the first width.

Each projection 106 a, 106 b, 106 c has at least one physical property.The first projection 106 a has a first length and a first width, thesecond projection 106 b has a second length and a second width, and thethird projection 106 c has a third length and a third width. As shown inFIG. 1, each projection 106 a, 106 b, 106 c comprises at least onedifferent physical property: the first length of the first projection106 a is longer than the second length of the second projection 106 b,and the second length of the second projection 106 b is longer than thethird length of the third projection 106 c. Because the first projection106 a, the second projection 106 b, and the third projection 106 ccomprise at least one different physical property, each projection 106a, 106 b, 106 c comprises a different resonance frequency. The resonancefrequency of the first projection 106 a is different than the resonancefrequency of the second projection 106 b because, at least in part, thefirst length is different than the second length. The resonancefrequency of the second projection 106 b is different than the resonancefrequency of the third projection 106 c because, at least in part, thesecond length is different than the third length.

Because the projections 106 a, 106 b, 106 c have different resonancefrequencies, each one of the projections may produce a different hapticfeedback effect when the projection is vibrated at its resonancefrequency. For example, a projection having a low resonance frequencymay produce a low rumble when actuated at its resonance frequency. Aprojection having a high resonance frequency may produce many smallvibrations when actuated at its resonance frequency.

In one embodiment, the resonance frequency of one projection may be amultiple of a resonance frequency of one or more other projections. Forexample, the first projection 106 a may have a resonance frequency of100 Hz, the second projection 106 b may have a resonance frequency of200 Hz, and the third projection 106 c may have a resonance frequency of400 Hz. In such an example, when the resonator 102 vibrates at 100 Hz,the first projection vibrates at its resonance frequency. When theresonator 102 vibrates at 200 Hz, both the first projection and thesecond projection vibrate at the resonance frequency of each projection.And when the resonator 102 vibrates at 400 Hz, each projection vibratesat its resonance frequency. Such an apparatus may be configured to layerand multiply haptic effects on top of each other in certain embodiments,for example to combine a low rumble haptic feedback effect with a highvibration haptic feedback effect.

In other embodiments, the resonance frequency of a first projection maynot be an integer multiple of a resonance frequency of any otherprojection. For instance, one apparatus may comprise a first projectionwith a first resonance frequency of 29 Hz, a second projection with asecond resonance frequency of 37 Hz, and a third projection with a thirdresonance frequency of 53 Hz. When each projection has a resonancefrequency that is a prime number and/or not a multiple of a resonancefrequency of any of the other projections, only one projection mayvibrate at its resonance frequency at one time. Such an apparatus may beconfigured to isolate specific feedback effects, for example, tomaximize a specific type of haptic feedback effect at one time.

The projections 106 a, 106 b, 106 c are shown as rectangles with a flat,regular surface and a uniform thickness. In other embodiments, theprojections may comprise different lengths, widths, thicknesses, shapes,surface characteristics, and/or other physical properties. For example,in one variation, a resonator may comprise a first oval-shapedprojection, a second circle-shaped projection, and a third square-shapedprojection. In another variation, a first projection may have a smooth,flat surface, while a second projection may have a surface comprising aplurality of bumps and/or ridges, or the surface may define a hole. Thephysical properties of a projections can affect the resonance frequencyof a projection. Thus, as the length or the composition or otherphysical property of two projections varies, so does the resonancefrequency of each.

In some embodiments, the resonator 102 comprises a uniformsubstance—that is, the base 104 and the projections 106 a, 106 b, 106 ccomprise the same substance. In another variation the base 104 and theprojections 106 a, 106 b, 106 c comprise a different substance. Forexample, the base 104 may comprise plastic substance, while theprojections 106 a, 106 b, 106 c comprise a metallic substance. In yetanother variation, each projection is coated with a different substance.A variation in substance may result in a variation in the resonancefrequency. For example, a first projection may be coated with an epoxyresin, and have a first thickness. A second projection may be coated ina polymer matrix, such as silicon, and have a second thickness differentthan the first thickness. And a third projection may be uncoated, andhave a third thickness different than the first thickness and the secondthickness.

Although the first length of the first projection 106 a, the secondlength of the second projection 106 b, and the third length of the thirdprojection 106 c are shown as different lengths in FIG. 1, in otherembodiments, two or more of the projections of the resonator 102 maycomprise the same length. The resonator 102 of the apparatus 100comprises three projections 106 a, 106 b, 106 c. In other embodiments,the resonator may comprise two, three, or more projections.

FIG. 2 is a perspective view of an apparatus for providing hapticfeedback at multiple resonance frequencies according to one embodimentof the present invention. As illustrated in FIG. 2, the apparatus 200comprises a resonator 202 and a piezoelectric actuator 208.

As shown in FIG. 2, the resonator 202 comprises a base 204 and aplurality of projections 206 a, 206 b, and 206 c. Each projection 206 a,206 b, 206 c has at least one physical property. The first projection206 a comprises a first width. The second projection 206 b comprises asecond width. The third projection 206 c comprises a third width. Asshown in FIG. 2, each of the plurality of projections 206 a, 206 b, 206c comprises at least physical property different than a physicalproperty of the other projections. In FIG. 2, the first width of thefirst projection 206 a is wider than the second width of the secondprojection 206 b. The second width of the second projection 206 b iswider than the third width of the third projection 206 c. Eachprojection 206 a, 206 b, 206 c has a different resonance frequency basedat least in part on the different width of each projection 206 a, 206 b,206 c.

The apparatus 200 also comprises a piezoelectric actuator 208 configuredto generate a haptic feedback effect. The piezoelectric actuator 208 iscoupled to a first surface of the base 204 of the resonator 202.Although not shown in FIG. 2, one or more piezoelectric actuators may becoupled to a second surface of the base 204. The piezoelectric actuator208 may be configured to generate a haptic feedback effect at each oneof the plurality of resonance frequencies of the plurality ofprojections 206 a, 206 b, 206 c.

FIG. 3 is a perspective view of an apparatus for providing hapticfeedback at multiple resonance frequencies according to one embodimentof the present invention. As shown in FIG. 3, the apparatus 300comprises a resonator 302 and a piezoelectric actuator 308. Theresonator 302 comprises a base 304, a first projection 306 a, a secondprojection 306 b, a third projection 306 c, a fourth projection 306 d,and a fifth projection 306 e.

The resonator 302 is shown in a symmetric configuration. Physicalproperties of the first projection 306 a, such as the length, width, andshape of the first projection 306 a, mirror the same physical propertiesof the fifth projection 306 e. Additionally, physical properties of thesecond projection 306 b, such as the length, width, and shape of thesecond projection 306 b, mirror the same physical properties of thefourth projection 306 d. A symmetrical resonator 302 may be easier todesign and/or manufacture. In some variations, a symmetrical resonator302 may provide more balanced haptic feedback effects across a hapticfeedback device than a non-symmetrical resonator.

The first projection 306 a has a first length and a first width; thesecond projection 306 b has a second length and a second width; thethird projection 306 c has a third length and a third width; the fourthprojection 306 d has a fourth length and a fourth width; and the firstprojection 306 e has a fifth length and a fifth width. As shown in FIG.3, each projection 306 a, 306 b, 306 c, 306 d, 306 e has the same width.That is, the first width, the second width, the third width, the fourthwidth, and the fifth width are the same. However, because not all of thephysical properties of each projection 306 a, 306 b, 306 c, 306 d, 306 eare the same, the resonance frequencies of the projections 306 a, 306 b,306 c, 306 d, 306 e are not all the same.

Since the first length of the first projection 306 a is equal to thefifth length of the fifth projection 306 e, the resonance frequency ofthe first projection 306 a is equal to the resonance frequency of thefifth projection 306 e, assuming all of the other physical properties ofthe projects are the same. Similarly, since the second length of thesecond projection 306 b is equal to the fourth length of the fourthprojection 306 d, the resonance frequency of the second projection 306 bis equal to the resonance frequency of the fourth projection 306 d. Incontrast, since the third length of the third projection 306 c is notthe same as the first, second, fourth, or fifth length, the resonancefrequency of the third projection 306 c is not the same as the resonancefrequency of these other projections first projection 306 a, 306 b, 306d, and 306 e.

The apparatus 300 also comprises a piezoelectric actuator 308 coupled toa top of a base 304 of the resonator 302. In one embodiment, a pluralityof actuators are coupled to opposing surface of the base 304. Thepiezoelectric actuator 308 is configured to generate a haptic feedbackeffect. For example, the piezoelectric actuator 308 may vibrate theresonator 302 at the resonance frequency of the second projection 306 band the fourth projection 306 d. The apparatus, including the secondprojection 306 b and the fourth projection 306 d, may then generateenhanced haptic feedback effects.

FIG. 4 is a side view of an apparatus for providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention. As shown in FIG. 4, the apparatus 400 comprises aresonator 402, a top piezoelectric actuator 408 a, and a bottompiezoelectric actuator 408 b. The resonator 402 comprises a base 404, afirst projection 406 a, a second projection 406 b, and a thirdprojection 406 c.

The first projection 406 a has a first length and a first thickness; thesecond projection 406 b has a second length and a second thickness; andthe third projection 406 c has a third length and a third thickness. Asshown in FIG. 4, each projection 406 a, 406 b, 406 c comprises the samethickness, i.e., the first thickness, the second thickness, and thethird thickness are the same. However, because each projection 406 a,406 b, 406 c comprises a different length, each projection 406 a, 406 b,406 c comprises a different resonance frequency. The resonance frequencyof the first projection 406 a is different than the resonance frequencyof the second projection 406 b based at least in part on the differencebetween the first length and the second length. The resonance frequencyof the second projection 406 b is different than the resonance frequencyof the third projection based at least in part on the difference betweenthe second length and the third length.

The apparatus 400 also comprises a first piezoelectric actuator 408 acoupled to a top of a base 404 of the resonator 402, and a secondpiezoelectric actuator 408 b coupled to a bottom of the base 404 of theresonator 402. Both the first piezoelectric actuator 408 a and thesecond piezoelectric actuator 408 b may be configured to provide hapticfeedback effects. For example, the piezoelectric actuators 408 a, 408 bmay cause one or more of the projections 406 a, 406 b, 406 c to bend orflex up and down. When the piezoelectric actuators 408 a, 408 b vibrateat a resonance frequency of at least one of the projections 406 a, 406b, 406 c, the apparatus 400 may generate enhanced haptic feedbackeffects. In some embodiments, piezoelectric actuators 408 a and 408 bmay be embedded within a flexible bonding material. In some embodiments,the flexible bonding material may act as an interface between thepiezoelectric actuator and the base. The flexible bonding material mayhave a specific stiffness and damping ratio, and may also allow movementin an additional degree of freedom. In such an embodiment, theadditional degree of freedom and the stiffness and damping ratio mayallow the system to operate at additional resonant frequencies. In someembodiments, the present invention may use these additional resonantfrequencies to generate additional haptic effects. In some embodiments,the flexible bonding material may comprise a polymer matrix such asepoxy.

In some configurations, a first apparatus for multiple resonancefrequency may be positioned in a complimentary arrangement with a secondapparatus for multiple resonance frequency. FIG. 5 is a top view of anapparatus for providing haptic feedback at multiple resonancefrequencies according to one embodiment of the present invention. Asshown in FIG. 5, the apparatus 500 comprises a first resonator 502 witha first piezoelectric actuator 508, and a second resonator 552 with asecond piezoelectric actuator 558. The resonator 502 comprises a base504 and five projections 506 a, 506 b, 506 c, 506 d, and 506 e. Theresonator 552 also comprises a base 554 and five projections 556 a, 556b, 556 c, 556 d, and 556 e.

The resonator 502 is shown in a complimentary configuration with theresonator 552. By using a plurality of resonators 502, 552, hapticfeedback effects may be enhanced. In one configuration, two or moreprojections may be configured to provide a haptic feedback effect to aparticular component of a device, such as a particular button, aparticular region of a display, or a particular section of a housing.For example, as shown in FIG. 5, projection 506 a and projection 556 amay be in communication with a first key of a housing. Both projection506 a and projection 556 a may be configured to provide a hapticfeedback effect to the first key. The longer projection 506 a may have ahigh resonance frequency, and be configured to provide high frequencyvibrations to the first key. The shorter projection 556 b may have a lowresonance frequency, and be configured to provide low frequencyvibrations to the first key. Projection 506 b and projection 556 b maybe in communication with a second key of the housing. In someembodiments (not shown in FIG. 5) the projections may not be in directmechanical contact with the keys of the housing. In such an embodimentthe resonant frequency may be transmitted through the air between thekey and the projection.

In some embodiments, piezoelectric actuator 558 may be embedded within aflexible bonding material. The flexible bonding material may have aspecific stiffness and damping ratio, and may also allow movement in anadditional degree of freedom. In such an embodiment, the additionaldegree of freedom and the stiffness and damping ratio may allow thesystem to operate at additional resonant frequencies. In someembodiments, the present invention may use these additional resonantfrequencies to generate additional haptic effects.

FIG. 6 is a top view of an apparatus for providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention. As shown in FIG. 6, the apparatus 600 comprises aresonator 602 with a piezoelectric actuator 608 and a haptic feedbacksurface 610. The resonator 602 comprises a base 604, a first projection606 a, a second projection 606 b, a third projection 606 c, and a fourthprojection 606 d.

As shown in FIG. 6, the first projection 606 a has a first length and afirst width; the second projection 606 b has a second length and asecond width; the third projection 606 c has a third length and a thirdwidth, and the fourth projection 606 d has a fourth length and a fourthwidth. Each projection 606 a, 606 b, 606 c, 606 d shown in FIG. 6 hasthe same width. However, because each projection 606 a, 606 b, 606 c,606 d is a different length, each projection 606 a, 606 b, 606 c, 606 dhas a different resonance frequency. In one alternative, each projection606 a, 606 b, 606 c, 606 d may be the same length, but comprise adifferent stiffness, and thus a different resonance frequency.

The projections 606 a, 606 b, 606 c, 606 d are each in communicationwith the haptic feedback surface 610. As shown in FIG. 6, the hapticfeedback surface is positioned under each of the projections 606 a, 606b, 606 c, 606 d. The haptic feedback surface 610 may comprise atouch-screen display, a keypad, keyboard, foot pad, or other surfaceconfigured to provide a haptic feedback effect. When the piezoelectricactuator 608 causes one or more of the projections 606 a, 606 b, 606 c,606 d to vibrate, then the haptic feedback surface 610 may providehaptic feedback effects to a user. For example, the piezoelectricactuator 608 may cause the third projection 606 c to vibrate or resonateat its resonance frequency. As the third projection 606 c vibrates, theprojection 606 c may cause the haptic feedback surface 610 to output ahaptic effect, such as a vibration.

FIG. 7 is a perspective view of an apparatus for providing hapticfeedback at multiple resonance frequencies according to one embodimentof the present invention. As shown in FIG. 7, the apparatus 700comprises a resonator 702, a first piezoelectric actuator 708 a, and asecond piezoelectric actuator 708 b. The resonator 702 comprises a base704 and nine projections 706 a, 706 b, 706 c, 706 d, 706 e, 706 f, 706g, 706 h, 706 i arranged in an array.

Each projection 706 comprises at least one physical property. In theillustration shown in FIG. 7, each projection 706 is attached or affixedto the base 704 with a different spring value. For instance, the springvalue of the connection between the first projection 708 a and the base704 may be higher than the spring value of the connection between thesecond projection 706 b and the base 704 a, and higher still than thespring value of the connection between the third projection 706 c andthe base 704. Because each projection 708 is attached to the base 704with a different spring value, each projection 706 may have a differentresonance frequency. In another embodiment, the spring value of eachprojection 706 is the same, but each projection 706 comprises adifferent thickness.

The piezoelectric actuators 708 may actuate the base 704 at a resonancefrequency of one of the projections 706. For example, the piezoelectricactuators 708 may actuate the base 704 at a resonance frequency of thefifth projection 706 e. By actuating the base 704 at a resonancefrequency of the fifth projection 706 e, the fifth projection 706 e maygenerate a targeted haptic feedback effect. In one variation, eachprojection 706 is in communication with a touch-screen display. When thepiezoelectric actuators 708 actuate at a resonance frequency of one ofthe projections, the targeted projection generates a localized hapticfeedback effect on the display corresponding to the position of theprojection on the base 704.

FIG. 8 is a block diagram of a system providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention. The system 800 comprises a haptic feedback device802, such as a mobile phone, mobile computer, personal digital assistant(PDA), portable media player, or portable gaming device. The hapticfeedback device 802 comprises a processor 810 in communication with anetwork interface 812, a sensor 814, a display 820, and a keypad 822.The processor 510 is also in communication with a piezoelectric actuator816 coupled to a resonator 518. The piezoelectric actuator 816 and theresonator 818 may provide haptic feedback effects to the display 820and/or the keypad 822.

The processor 810 is in communication with the network interface 812.The network interface 812 may comprise one or more methods of mobilecommunication, such as infrared, radio, Wi-Fi or cellular networkcommunication. In other variations, the network interface 812 comprisesa wired network interface, such as Ethernet. The haptic feedback device802 can be configured to exchange messages with other devices (notshown) over networks such as a cellular phone network and/or theInternet. Embodiments of messages exchanged between devices may comprisevoice messages, text messages, data messages, or other forms ofmessages.

The processor 810 is also in communication with one or more sensors 814.The sensor 814 may comprise a location sensor, rotational velocitysensor, image sensor, pressure sensor, or other type of sensor. Forexample, sensor 814 may comprise an accelerometer, a gyroscope, a GPSsensor, a touch-sensitive input device (e.g. touch screen, touch-pad),or some other type of sensor. The one or more sensors 814 may beconfigured to detect changes in, for example, acceleration, inclination,inertia, or location. For example, the haptic feedback device 802 maycomprise an accelerometer configured to measure acceleration of thehaptic feedback device 802. As another example, the haptic feedbackdevice 802 may comprise a location sensor, rotary velocity sensor, imagesensor, pressure sensor, or other type of sensor. The one or moresensors 814 may be configured to send a sensor signal to the processor810.

The processor 810 is in communication with a display 820 and a keypad822. The display may comprise a touch-sensitive input device, such as atouch-screen. The actuator 816 and the resonator 818 may be configuredto provide haptic feedback effects to the display 820 and/or the keypad822. In other embodiments, the actuator 816 and the resonator 818 mayprovide haptic feedback effects to other parts of the haptic feedbackdevice 802, such as a touch-pad (not shown in FIG. 8) and/or anoff-activating area (not shown in FIG. 8).

The processor may determine a haptic feedback effect based at least inpart on a sensor signal received from the sensor 814, a display signalreceived from the display 820, and/or an input signal received from thekeypad 822. As one example, the processor may be generating a game shownon the display 820. When a virtual object is destroyed in the game,perhaps through some input received from the keypad 822 or touch-screendisplay 820, the processor may determine a haptic feedback effectimitating an explosion, such as a heavy rumble.

FIG. 9 is an illustration of a system providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention. The system 900 in FIG. 9 comprises a mobile phone.The mobile phone comprises a body 902, a display 904, and a keypad 906.The mobile phone also comprises a processor (not shown in FIG. 9) incommunication with a piezoelectric actuator (not shown in FIG. 9). Thepiezoelectric actuator is coupled to a resonator (not shown in FIG. 9)in communication with the keypad 906.

The resonator may comprise a plurality of projections, each projectionwith a different resonance frequency, such as those described in variousembodiments herein. The piezoelectric actuator and the resonator may beconfigured to generate haptic feedback effects on the keypad 906. Whenthe piezoelectric actuator actuates the resonator at a resonancefrequency of at least one of a plurality of projections of theresonator, then the at least one projection may generate enhanced hapticfeedback effects, such as by bending or flexing with lower powerconsumption but increased strength.

FIG. 10 is an illustration of a system providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention. The system 1000 in FIG. 10 comprises a mobile phone.The mobile phone comprises a body 1002, a touch-screen display 1004, anda keypad 1006. The mobile phone also comprises a processor (not shown inFIG. 10) in communication with a piezoelectric actuator (not shown inFIG. 10). The piezoelectric actuator is coupled to a resonator (notshown in FIG. 10) in communication with the touch-screen display 1004.

The piezoelectric actuator and the resonator may be configured togenerate haptic feedback effects on the touch-screen display 1004. Forexample, when the piezoelectric actuator actuates the resonator and aplurality of projections at a resonance frequency of at least one of theplurality of projections, then the at least one projection may generateenhanced haptic feedback effects, such as by bending or flexing withlower power consumption but increased strength.

FIG. 11 is a flow diagram of a method providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention. The elements of the system 1100 are described withreference to the system depicted in FIG. 8. A variety of otherimplementations are possible. The method 1100 begins with the processor810 receiving an input signal 1102. The processor 810 may receive theinput signal from a touch-screen display 820, a keypad 822, a sensor814, or from some other source. In one example, a user is playing avideo game on the haptic feedback device 802. During game play, the useractivates a button on the keypad 822 and the processor 820 receives aninput signal from the keypad 822 associated with the button activation.

Next, the processor 810 determines a haptic feedback effect based atleast in part on the input signal 1104. In one embodiment, an inputsignal received from a keypad 822 may be associated with an interactionon the display 820. The processor 810 may determine a haptic feedbackeffect simulating the interaction on the display 820. In one embodiment,the processor 810 selects a haptic feedback effect from a library ofhaptic feedback effects stored in a local memory.

Next, the processor 810 selects at least one projection of a pluralityof projections of a resonator to output the haptic feedback effect basedat least in part on a resonance frequency of the at least one projection1106. The resonator 818 may comprise a plurality of projections, eachprojection having a different resonance frequency. The processor 810 mayselect which projection to output the haptic effect by determining whichprojection is best suited to output the haptic feedback effect. Forexample, the resonance frequencies of the projections may be stored in alookup table or other data store in which the processor 810 searches forthe resonance frequency associated with each projection. For example, ifthe processor 810 determines a haptic feedback effect such as a low,deep rumble, the processor 810 may select a projection having the lowestresonance frequency of the plurality of projections of the resonator818. As another example, if the processor 810 determines a hapticfeedback effect such as a light, fast tapping effect, the processor 810may select the projection having the highest resonance frequency of theplurality of projections of the resonator 818.

Finally, the processor 810 generates a haptic signal configured to causethe piezoelectric actuator 816 to generate a haptic feedback effect atthe resonance frequency 1108. After receiving a haptic signal, thepiezoelectric actuator 816 may vibrate at a frequency associated withthe haptic signal. By generating a haptic feedback effect at theresonance frequency of one of the projections, the vibration or bendingof the projection may be stronger and/or more efficient than if thevibration was not at the resonance frequency of one of the projections.Thus, the haptic feedback effect at the resonance frequency of aprojection may consume less power and/or be more amplified than a hapticfeedback effect at a non-resonance frequency of a projection.

FIG. 12 is a flow diagram of a method providing haptic feedback atmultiple resonance frequencies according to one embodiment of thepresent invention. The method 1200 begins with providing a resonatorcomprising a base and a plurality of projections, at least two of theplurality of projections having a different resonance frequency 1202.The resonator may comprise a symmetric configuration or an asymmetricconfiguration. In a symmetric configuration, a first half of theresonator may mirror a second half of the resonator. In one instance ofa symmetric configuration, a resonator comprises two projections: afirst projection may have the same size and shape as a second projectionopposite the first projection. In an asymmetric configuration, a firstprojection may have a different size and/or shape than a secondprojection opposite the first projection.

Next, the method 1200 comprises coupling a piezoelectric actuator to theresonator 1204. The piezoelectric actuator may be coupled to theresonator via an epoxy resin, via mechanical means, or via some othermethod. One or more piezoelectric actuators may be coupled to the top ofthe resonator, and one or more piezoelectric actuators may be coupled tothe top of the resonator.

Embodiments of the present invention can be implemented in combinationwith digital electronic circuitry, or in computer hardware, firmware,software, or in combinations of them. In one embodiment, a computer suchas a mobile phone may comprise a processor or processors. The processorcomprises a computer-readable medium, such as a random access memory(RAM) coupled to the processor. The processor executescomputer-executable program instructions stored in memory, such asexecuting one or more computer programs for messaging. Such processorsmay comprise a microprocessor, a digital signal processor (DSP), anapplication-specific integrated circuit (ASIC), field programmable gatearrays (FPGAs), and state machines. Such processors may further compriseprogrammable electronic devices such as PLCs, programmable interruptcontrollers (PICs), programmable logic devices (PLDs), programmableread-only memories (PROMs), electronically programmable read-onlymemories (EPROMs or EEPROMs), or other similar devices.

Such processors may comprise, or may be in communication with, media,for example, computer-readable media that may store instructions that,when executed by the processor, can cause the processor to perform thesteps described herein as carried out, or assisted, by a processor.Embodiments of computer-readable media may comprise, but are not limitedto, an electronic, optical, magnetic, or other storage or transmissiondevice capable of providing a processor, such as the processor in a webserver, with computer-readable instructions. Other examples of mediacomprise, but are not limited to, a floppy disk, CD-ROM, magnetic disk,memory chip, ROM, RAM, ASIC, configured processor, all optical media;all magnetic tape or other magnetic media, or any other medium fromwhich a computer processor can read. Also, various other devices mayinclude computer-readable media, such as a router, private or publicnetwork, or other transmission device. The processor, and theprocessing, described may be in one or more structures, and may bedispersed through one or more structures. The processor may comprisecode for carrying out one or more of the methods (or parts of methods)described herein.

GENERAL

The foregoing description of the embodiments, including preferredembodiments, of the invention has been presented only for the purpose ofillustration and description and is not intended to be exhaustive or tolimit the invention to the precise forms disclosed. Numerousmodifications and adaptations thereof will be apparent to those skilledin the art without departing from the spirit and scope of the invention.

That which is claimed is:
 1. An apparatus comprising: a resonatorcomprising a base and a plurality of projections, a first projection ofthe plurality of projections having a first resonance frequency and asecond projection of the plurality of projections having a secondresonance frequency different from the first resonance frequency; and apiezoelectric actuator coupled to the resonator and operable to output ahaptic feedback effect at the first resonance frequency and at thesecond resonance frequency.
 2. The apparatus of claim 1, wherein eachone of the plurality of projections comprises a physical property. 3.The apparatus of claim 2, wherein the physical property comprises ashape, a length, a width, a thickness, a surface, a materialcomposition, or a material coating.
 4. The apparatus of claim 2, whereinthe physical property comprises an irregular surface, having a bump ordefining a hole.
 5. The apparatus of claim 1, wherein a physicalproperty of the first projection comprises a first physical property andthe second projection comprises a second physical property differentfrom said first physical property.
 6. The apparatus of claim 5, whereinthe first physical property comprises a first length and wherein thesecond physical property comprises a second length different than thefirst length.
 7. The apparatus of claim 1, wherein the first resonancefrequency is not an integer multiple of the second resonance frequency.8. The apparatus of claim 1, wherein the plurality of projections arecoupled to the base.
 9. The apparatus of claim 1, wherein the resonatorcomprises a first surface and a second surface and wherein thepiezoelectric actuator comprises: a first piezoelectric actuator coupledto the first surface; and a second piezoelectric actuator coupled to thebottom surface.
 10. The apparatus of claim 1, wherein the piezoelectricactuator is coupled to the resonator via an epoxy resin.
 11. Theapparatus of claim 1, wherein the piezoelectric actuator is coupled tothe resonator via a flexible mounting.
 12. The apparatus of claim 1,wherein the piezoelectric actuator is configured to: receive a hapticsignal from a processor; and generate a haptic feedback effect at aresonance frequency of at least one of the plurality of projections inresponse to the signal.
 13. An apparatus comprising: a resonatorcomprising: a base, having a first surface and a second surface; a firstprojection coupled to the base and having a first length and a firstresonance frequency, a second projection coupled to the base and havinga second length and a second resonance frequency, the second lengthdifferent than the first length, the second resonance frequencydifferent from the first resonance frequency; a third projection coupledto the base having a third length and a third resonance frequency, thethird length different from the second length and different from thefirst length, the third resonance frequency different from the secondresonance frequency and the first resonance frequency; a firstpiezoelectric actuator coupled to the first surface; a secondpiezoelectric actuator coupled to the second surface; and wherein thefirst piezoelectric actuator and the second piezoelectric actuator areconfigured to receive one or more haptic signals from a processor and togenerate a haptic feedback effect at one or more of the first resonancefrequency, the second resonance frequency, and the third resonancefrequency.
 14. The apparatus of claim 13, further comprising an inputdevice in communication with the processor.
 15. The apparatus of claim14, wherein the apparatus comprise one of a mobile phone, mobilecomputer, a personal digital assistant (PDA), a portable media player,or a portable gaming device.
 16. A method comprising: receiving an inputsignal; determining a haptic feedback effect based at least in part onthe input signal; selecting at least one projection of a plurality ofprojections of a resonator to output the haptic feedback effect based atleast in part on a resonance frequency of the at least one projection;and generating a haptic signal configured to cause a piezoelectricactuator coupled to the resonator to generate a haptic feedback effectat the resonance frequency.
 17. The method of claim 16, furthercomprising receiving the haptic signal and generating the hapticfeedback effect.
 18. The method of claim 16, wherein selecting at leastone projection of a plurality of projections of a resonator comprisesselecting a projection based at least in part on the haptic feedbackeffect to be output.
 19. A non-transitory computer-readable medium onwhich is encoded processor-executable program code, the program codecomprising: program code to receive an input signal; program code todetermine a haptic feedback effect based at least in part on the inputsignal; program code to determine at least one projection of a pluralityof projections of a resonator to output the haptic feedback effect basedat least in part on a resonance frequency of the at least oneprojection; and program code to generate a haptic signal configured tocause a piezoelectric actuator coupled to the resonator to generate ahaptic feedback effect at the resonance frequency.
 20. Thenon-transitory computer-readable medium of claim 19, wherein the programcode to determine at least one projection of a resonator to output thehaptic feedback effect comprises program code to select a projectionbased at least in part on the haptic feedback effect to be output.